Sorbic acid (2,4-hexadienoic acid) is widely used as a preservative in foods and beverages. A common problem when using sorbic acid in beverage applications is low solubility in syrups and finished beverages.
Because of its low solubility, sorbic acid is unstable in syrups and finished beverages resulting in creaming and precipitates. For example, the solubility of sorbic acid in water at room temperature is 0.16 wt %. The solubility of sorbic acid in a solution containing 60 wt % sugar is 0.08 wt %. The solubility of sorbic acid in high acid syrup is less than 0.1 wt %.
It is desired to have at least 1200-1600 ppm sorbic acid in syrups and at least 200-250 ppm in finished beverages, but such amounts have been difficult to achieve due to low solubility, creaming, settling, precipitation, and phase separation.
Likewise benzoic acid is a widely used preservative but also has low solubility in concentrated syrup and finished beverage; thus it is also desired to increase the solubility of benzoic acid in syrups and finished beverages.